def main():
    s = list(input())
    f = False
    for i, c in enumerate(s):
        if f:
            s[i] = "9"
        elif c=="3":
            s[i] = "2"
            f = True
    ans = int("".join(s))
    while ans%3==0:
        ans -= 1
    print(ans)


if __name__ == "__main__":
    main()